1. Field of the Invention
This invention relates to a flash device suitable for use with a camera.
2. Description of the Prior Art
A flash device for a camera normally includes a light emitter unit, a capacitor, a flash circuit and a casing as principal components. A built-in auxiliary light unit is provided in some flash devices for automatic focusing cameras. A light emitter unit is composed of a reflector, a xenon tube and so on and is normally disposed so as to assure a maximum distance between a light emitting section of the light emitter unit and an optical axis of a photographing lens of a camera in order to minimize or eliminate a read-eye phenomenon.
To this end, some known cameras have a shiftable casing section mounted for shifting movement on a body casing section to and from an operative position in which a light emitter section mounted in the shiftable casing section is projected outside the body casing section. In most of such known cameras, shifting movement of the shiftable casing section must be performed by manual operation of a user.
Meanwhile, some known flash devices are designed so as to change over the light distribution angle thereof in accordance with a focal length of a photographing lens of a camera in order to make use of light energy more effectively. Such flash devices are on the market as flash devices of a comparatively large size, and most of them are of the manually operated type.
In recent years, built-in type flash devices have been developed which include means for controlling a light emitting section by means of a motor. In such flash devices, rotation of the motor is transmitted by way of a gear train to shift the light emitting section up or down by means of a cam element provided at the final stage of the gear train.
However, a structure suitable for use with a flash device of a small size for changing over the light distribution angle in accordance with a focal length of a photographing lens of a camera has not yet been provided. A flash device which includes both a shifting mechanism for a light emitter unit and a mechanism for automatically changing over the light distribution angle has not yet been developed either.
Meanwhile, a flash device for a camera is already known wherein a light emitting section provided in a camera body is shifted up or down by a motor means.
Such mechanism for controlling shifting movement of a light emitting section by means of a motor has not been developed for nor employed in a clip-on type flash device unit which can be removably mounted at a shoe seat thereof on an accessory shoe of a body of a camera such as a single lens reflex camera.